Fig. 1. Schematic illustration of ¹⁹F/¹H-CEST dual-imaging modality Gly-PFOBs.

The precision imaging-guided RT-sensitized strategy utilizes glycerol-weighted and PFOB-based CEST nano-molecular imaging probes, known as Gly-PFOBs. In this strategy, (i) Gly-PFOBs with O₂ and pH dual sensitive properties dynamically reflect the changes in tumor hypoxia and acidic microenvironment, (ii) the high oxygen-carrying characteristic of Gly-PFOBs effectively improves tumor hypoxia and exerts maximum synergistic radiotherapeutic effects, and (iii) the real-time and non-invasive ¹⁹F/¹H-CEST dual-modality MR imaging enables the identification of an optimized radiotherapy time window (ORTW) for precision radiotherapy.